Diverse coral reef yields many new species despite threat of silver mine

A vast array of new species was recently discovered in the world's most spectacular reef you've never heard of -- Madang Lagoon in Papua New Guinea.

"It is the most diverse reef in the world," said marine biologist Jim Thomas, a researcher at Nova Southeastern University's National Coral Reef Institute in Hollywood, Fla.

Madang Lagoon is also one of the world's most threatened coral reefs, Thomas added, imperiled by nearby industry. A World Bank-sponsored tuna cannery opened recently, drawing tiger sharks attracted to offal dumped offshore. Another 10 canneries are planned, Thomas said. Along the Ramu River, which drains into the lagoon, a massive nickel mine just started operation. The mining company dumps its sludge a mile offshore, but Thomas is concerned the sediment could contaminate the lagoon.

A new amphipod species from Madang Lagoon. The tiny, shrimp-like creature lives inside a clam.

An international team surveyed Madang Lagoon's coral reefs in December 2012, to document changes since the last survey 20 years ago and provide a baseline for any changes due to development. Biologist Philippe Bouchet of the Natural History Museum in Paris led a lagoonwide survey, while Thomas and his colleagues returned to the site of their expedition in the 1990s.

The good news is that despite the ensuing development, the reef is as diverse as it was 20 years ago, Thomas said. In fact, both teams found new marine creatures.

Because they revisited the same sites, Thomas' team, which searched for invertebrates, knew right off they had discovered new species, he said. These include amphipods, tiny shrimplike creatures that live inside sponges and clams, and fernlike crinoids, which grip the coral. A new pink nudibranch, a snail without a shell, was also found. The French group also documented a wide array of new species, which await publication in scientific journals.

Though the invertebrates monitored at Madang Lagoon aren't as photogenic as flashy fish, the species are important indicators of reef health and biodiversity, Thomas said. "When an impact hits a reef, these species are the first to disappear, while coral may take five, 10, 15 years," he explained. "Most of the time, when something bad happens, by the time it hits the coral it's too late."

Jim Thomas

This new crinoid species was discovered in Madang Lagoon.

Thomas thinks Madang Lagoon acquired its species diversitythough its unusual geologic setting. The lagoon sits on the northern coast of Papua New Guinea, an island roughly the size of California, where two of Earth's tectonic plates collide. As the Pacific plate slammed volcanic islands into Papua New Guinea over the millennia, species hitching a ride added to the diversity.

The researchers hope local clans that own the lagoon will use the species survey to protect the reef against the effects of development. "These multinational companies can overwhelm landowners, and they really have no recourse," Thomas said.